WO2008030204A1

WO2008030204A1 - Electro-mechanical brake actuator

Info

Publication number: WO2008030204A1
Application number: PCT/TR2007/000086
Authority: WO
Inventors: Ahmet Akin; Yavuz Battal; Cuneyt Tengerli; Mustafa Evren Baykara; Murat Agagunduz
Original assignee: Arfesan Arkan Fren Elemanlari Sanayi Ve Ticaret A. S
Priority date: 2006-09-05
Filing date: 2007-09-04
Publication date: 2008-03-13

Abstract

This invention is related to three design of spring brake actuators used in heavy commercial vehicles. In this invention, parking brake force of the actuator is created through both air and electric motor or only electric motor. In the electromechanical brake actuators developed through this invention all types of spring brake power can be obtained with one type of park chamber design. Furthermore, developed designs provide significant advantages in the diagnosis of possible errors which may occur in the actuator.

Description

ELECTRO-MECHANICAL BRAKE ACTUATOR

FIELD OF INVENTION

This invention is related to new designs that are used in heavy commercial vehicles (HCV). Parking brake force of the actuator in this invention is created either only by electric motor or both air and electric motor. In other words, various designs having the same function are explained in the invention.

In the design where the parking brake force is created only by the electric motor, the electric motor placed in the park chamber of the actuator is activated when the handbrake is pulled. Electric motor is mechanically connected to the shaft by means of a planetary gear system. The said geared system increases the torque while decreasing the engine speed. Thus, the expected parking brake force is achieved. In another design where both air and electric motor are used, both compressed air is transmitted to the service chamber of the actuator and electrical motors placed on the park side are activated. Parking brake force is exerted to fix the vehicle through the transmitted compressed air. The said parking brake force is fixed, when the tube activated by the electrical motors leans against the flange. The air inside the service chamber is not released and the electrical motors remains activated until the system becomes stationery. In case of possible decrease in the force due to the cooling in the brake system, electrical motors operate and reestablish the targeted brake force. After the system becomes stationery, the compressed air in the service chamber is released and electrical motors are shut off, thereby ending the parking process. In this invention, compressed air and electrical motor are used in combination to exert the parking force.

In spring brake actuators used in commercial vehicles, a heavy spring which is called emergency spring is available in the actuator in order to slow down the vehicle when it lacks compressed air or to fix the vehicle when parking. The said spring is pressed when there is air pressure in the system. In case of an emergency such as air leakage or parking request, the vehicle is decelerated and stopped by means of the energy stored in the compressed emergency spring.

Park chamber functions with air pressure in the spring brake actuators which are currently in use. Park chamber volume and air consumption is high. In addition, more than one spring brake actuator is used on a vehicle depending on the type of the vehicle. This considerable excess amount of volume has a great impact on determining the size of the whole brake system. The higher the volume is, the larger, heavier and more costly will be the air tanks, compressor and some valves of the brake system. Particularly air tanks are not only large in size but also heavy at considerable weight.

Compressed air used in vehicles is produced by a compressor connected to the motor. Thus, use of higher amount of air results in the consumption of higher amount of fuel for the production of air by the motor. In addition, compressor to be utilized for covering the consumption of higher amount of air will be therefore large in size and heavy.

Considering the increasing amount of equipment and restrictions of weight, it is not desirable that the weight and volume of the parts are high. Taking into account of all these factors, decrease of air consumption in commercial vehicles, saving in terms of weight, volume and fuel, and low costs will contribute to both the final user and manufacturer and nature with less damage to the environment. PRIOR ART

There are two main parts called as park chamber and service chamber in the existing spring brake actuators. These two parts are divided by the adapter plate. There is a very strong spring in the park chamber of the actuator. The said spring produces the parking force required to fix while parking the vehicle. Emergency spring is compressed while in driving position. The spring is compressed by filling the compressed air to the volume (park chamber) between the piston and the adapter plate. When it is requested to fix the vehicle or in case of air leakage, compressed air in the park chamber is released. Consequently, emergency spring is released and brake force required for the fixation of the vehicle is obtained. OBJECTIVES FOR THE DEVELOPMENT OF THE INVENTION

In developing electro-mechanical brake actuator, which has been developed with this invention, it was aimed;

• To provide all types of emergency forces with a stationary design of parking section (Type 16, 24, 30 etc.),

• To diagnose easily any problem which may occur in the actuator,

• To reduce the size of actuator and to save space in the vehicle,

• To minimize consumption of pressurized air depending on the brake actuators on the vehicle,

- To reduce the weight of tools and equipments used to produce and store the pressurized air on the vehicle,

• To command the motors from a single center and through an arm or button in the driver's cabin,

• To fix the brake force applied to the brake discs constant, • To make the vehicle ready to start in a short period when being parked through low reaction time of the electric motors.

DESCRIPTION OF THE FIGURES

The description of the figures which are prepared in order to better explain the electro-mechanical brake actuators, which have been developed with this invention, are given below.

Figurel- Cross sectional drawing of Electro-Mechanical Brake Actuator (Design 1)

Figure 2- Exploded drawing of Electro-Mechanical Brake Actuator (Design 1)

Figure 3- Block diagram of the operation of the actuator (parking condition) (Design 1)

Figure 4- Block diagram of the operation of the actuator (driving conditions) (Design 1),

Figure 5- General view of Electro-Mechanical Brake Actuator (Design 2), Figure 6- Cross sectional drawing of Electro-Mechanical Brake Actuator (Design 2),

Figure 7- Perspective drawing of the connection between the Guide and the Threaded tube (Design 2),

Figure 8- Cross sectional drawing of Electro-Mechanical Brake Actuator (parking condition) (Design 2),

Figure 9- Block diagram of the operation of the actuator (parking condition) (Design 2),

Figure 10- Block diagram of the operation of the actuator (driving conditions) (Design 2)

Figure 11- General view of Electro-Mechanical Brake Actuator (Design 3),

Figure 12- Block diagram of the operation of the actuator (parking condition) (Design 3),

Figure 13- Block diagram of the operation of the actuator (driving conditions) (Design 3), Figure 14- Block diagram of the operation of the actuator (Emergency Park - Mechanical Breakdown) (Design 3)

DESCRIPTION OF THE PARTS-SECTIONS- OF THE INVENTION

The description of the parts- sections- components which are covered in the figures that are prepared in order to better explain the diaphragm electromechanical actuator with, which have been developed with this invention, are separately numbered and given below.

1. Electro-Mechanical Brake Actuator

2. Service Chamber 3. Diaphragm

4. Flange

5. Non pressure plate

6. Push rod 7. Adapter Plate

8. Plug

9. Air Inlet

10. Park Chamber 11. Housing (Design 1)

12. Electric motor (Design 1)

13. Motor output shaft (Design 1) 14.Transmission Shaft (Design 1) 15.Tube (Design 1) 16. Square nut (Design 1)

17. Guide shaft (Design 1)

18. Guide plate (Design 1)

19. Planet gears (Design 1)

20. Sun / Pinion gear (Design 1) 21. Ring gear (Design 1)

22. Bearing pins (Design 1)

23. Load cells

24. Lower and Upper Carrying Arms (Design 1)

25. ECAN Interface (Design 2) 26. Electrical Motor (Design 2)

27. Motor shaft (Design 2)

28. Pinion gear (Design 2)

29. First grade planetary gears (Design 2)

30. Second grade planetary gears (Design 2) 31. Spindle (Design 2) 32. Guide (Design 2)

33. Bearing (Design 2)

34. Housing (Design 2)

35. Threaded tube (Design 2) 36. Indented Part of Guide (Design 2)

37. Canals inside of Threaded tube (Design 2)

38. Threaded Part of Adapter Plate (Design 2)

39. Electrical Motors (Design 2)

40. Motor output shaft (Design 2) 41. Pinion Gears (Design 3)

42. First grade planetary gears (Design 3) 42.a Planet gears (Design 3)

42.b. Sun gear / Main Gear (Design 3)

43. Second grade planetary gears (Design 3) 43.a Planet gears (Design 3)

43. b Sun gear / Carrying Arm of the first grade planetary gears (Design 3)

44. Ring Gear (Design 3)

45. Carrying Arm of the Second grade planetary gears (Design 3)

46. Power Transmission Shaft (Design 3) 47. Tube (Design 3)

48. Square bearing part in the Center of Adapter Plate (Design 3)

49. Release Nut (Design 3)

50. Housing (Design 3) BRIEF DESCRIPTION OF THE INVENTION

Parking brake force of the actuator developed with this invention is created either only by means of electrical motor or through both air and electric motor. Parking brake is activated through an arm or button in driver's cabin. By pressing on the button or pulling the arm in the cabin, the parking or non-parking request is transmitted to the actuator through CAN (Controller Area Network). ECAN unit (Enhanced Controller Area Network) of the actuator having received this message operates the actuator according to the relevant flow diagram and fulfills the request to take the vehicle into parking or non-parking condition. In designs where parking brake force is created only by electrical motor, when the button in the cabin is pressed to park the vehicle, electrical motor inside the park chamber of the actuator is activated. Electrical motor output shaft having received this first movement conveys to one graded planetary gear system, thereby increasing the torque of the motor. Afterwards, this movement with increased torque is further conveyed to the transmission shaft from the planetary gear system. Rotary motion created by the motor in this part is converted into axial motion, thereby transmitting the brake force to the push rod of the actuator in other words to the wheels of the vehicle.

In designs where parking brake force is created through both compressed air and electrical motor, parking brake force is exerted by sending pressurized air at predetermined amount (this amount is arranged according to the parking type of the actuator) to service chamber. Motor in the park chamber is activated simultaneously with the inlet of air to the service chamber. Tube operated by mechanical connection to the motor, moves along with the stroke of the actuator; leans against the flange in the service chamber; and fixes the existing brake force.

The air in the service chamber is not released and motors are activated until the system becomes stationary (until the brake system cools down). In case of any possible decrease which may occur in the braking force within this period, motors are activated and increase the braking force up to the target value. Once the system is stationary, the air in the service chamber is released and parking process is completed. As it is previously mentioned, entire information required by the actuator to fulfill its functions is conveyed to the actuators through CAN (Controller Area Network) data line. ECAN interface (Enhanced Controller Area Network) integrated on the actuator receives this data, processes the data according to the related block diagrams, and ensures to get parking or non-parking condition to the actuator. In addition, brake actuator may be easily adapted to the (ECU) (Electronic Control Unit) of the current vehicles and controlled. Thus, possible problems on the actuator may be diagnosed and some significant information regarding the actuator may be saved in the ECU. Furthermore, errors on the actuator may be displayed on the screen of the vehicle's cabin and thereby warning the driver.

In electro-mechanical brake actuator designs where the parking brake force is created through both air and electrical motor, brake force is related to the area of the diaphragm in the service chamber and air pressure sent to this chamber of the actuator. Provided that the area of the diaphragm in the service chamber is fixed, parking brake force will be related to only the air pressure transmitted to the service chamber. Increasing the air pressure sent to the service chamber will further increase the parking brake force. Thus, brake force may be achieved at various values in the park chamber with the same design of the service chamber. In other words, if the service chamber of the actuator in this invention is Type 16 (T16), brake force of spring brake actuators at 16/16, 16/24, 16/30 and other intermediate values may be achieved. In another design where the parking brake force is formed by using only the electrical motor, all types of spring forces may be produced by making different motor controls.

In vehicles where existing spring brake actuators are used, activation of the vehicle will take time when the air tanks are empty or air pressure is low. However, in the design developed with this invention since the air volume required to activate the vehicle is relatively low, the vehicle becomes ready to shift from parking status to activated status. Furthermore, in case of a vehicle whose air tanks are depleted or tank pressure is decreased is used in the spring brake actuators mentioned in this invention, the air tanks will achieve the required pressure in a very short time as it will necessitate lesser amount of air. Therefore, the vehicle will be activated more rapidly. Another significant advantage of the actuator is that it occupies less space compared to its equivalents.

The electro-mechanical brake actuators developed with this invention are compatible with wiring of existing towing vehicle, truck and bus due to being operated voltage of 24V.

DETAILED DESCRIPTION OF THE INVENTION

Parking functions of electro-mechanical brake actuator (1), developed with this invention, are performed either only by electrical motor (12, 26, 39) or through both electrical motor (12, 26, 39) and air. EΞxisting brake actuators park functions by a heavy emergency spring placed in the park chamber (10) of the actuator. The electro-mechanical brake actuators (1) having three different designs developed with this invention comprises the main parts

Design 1: Electrical motor (12) used in this invention provides the motion required for the parking function of the actuator (1). When a button inside the vehicle is pressed or handbrake is pulled, the actuator (1) moves according to the block diagram shown in Figure 3. Initially, electrical motor (12) operates and pinion gear (20) connected to the motor output shaft (13) starts to rotate. As it can be seen in Figure 1 and 2, the said pinion (20) further rotates the planet gears (19) in which it is in contact. Planet gears (19) are placed between the carrying upper arm (24) and carrying lower arm (24) by means of the bearing pins (22). Planet gears (19) can freely rotate around these two carrying arms (24). Ring gear (21) which is connected to the planetary gears (19) are fixed to the housing (11) by bolts. As the ring gear (21) is fixed to the housing (11), motion on the planet gears (19) can be transmitted to the carrying arms (24). As seen in Figure 1, together with the carrying arms (24), transmission shaft (14) mechanically connected to these arms also rotate. Upper part of the transmission shaft (14) is completely formed by screw thread. Transmission shaft (14) operates reciprocally with the square nut (16). Square nut (16) is compressed between the guide plate (18) and the tube (15). Guide plate (18) and tube (15) are fixed to each other with threads. When the transmission shaft (14) rotates, the system comprising the square nut (16), the guide plate (18) and the tube (15) will seek to rotate around its own axis. Guide shafts (17) are used to prevent this system (16, 15, 18) from rotating around its axis. These shafts (17) also provide guidance to allow the guide plate (18) move in the vertical direction (in the direction of A and B). Guide shafts (17) are fixed on to the ring gear (21). When the transmission shaft (14) rotates in the predetermined direction, the system comprising the square nut (16), the tube (15) and the guide plate (18) will start to move in "A" direction. Upon the plug (8) connected to the upper part of the tube (15) with threads leans against the diaphragm (3) and flange (4), spring force is produced. The said force can be detected by the load cells (23) located on the plug (8). Motors (12) are stopped when the measured value of load attains the predetermined parking brake force. After this stage, it is waited until the system becomes stationary. In case of any loss in the amount of load during this period, electrical motors (12) are activated again and achieve the targeted parking brake force (Figure 3).

When it is requested to shift the vehicle into the driving condition, electro- mechanical brake actuator (1) moves according to the block diagram shown in Figure 4. In the first step, the motor (1) rotates in the opposite of the predetermined direction, thereby revolving the pinion gear (20), planet gears (19), bearing arms (24) and transmission shaft (14) in the opposite direction of the initial motion (parking motion). In this case, the system consisting of the guide plate (18), the square nut (16) and the tube (15) move in "B" direction. When the motion starts in "B" direction, load on the plug (8) starts to reduce. The value of load is regularly controlled by load cells (23) on the plug (8). When the value of force is zero, electrical motors (12) are stopped and the process to shift the vehicle to driving condition is terminated (Figure 4). Design 2: While producing the parking brake force in the electro-mechanical brake actuator (1) developed with this invention and shown in Figure 5, both compressed air and electrical motor operate in combination. In general, parking process works as follows: when it is requested to park the vehicle, compressed air is sent to the service chamber (2) of the actuator (1) from the air inlet (9). The compressed air starts to fill in the chamber (2) and diaphragm (3) made of rubber material overturns and pushes the flange (4) and push rod (6) connected to the flange (4) forward. Parking brake force is achieved when the flange (4) leans against the non pressure plate (5).

When it is requested to take the actuator (1) into the parking condition, it moves according to the block diagram shown in Figure 9. Initially, compressed air is sent to the service chamber (2) of the actuator (1) and simultaneously electrical motors (26) placed in the park chamber (10) are activated. As seen in Figure 6, this motion is firstly transmitted to the pinion gear (28) connected to the motor shaft (27). Pinion gear (28) having received this motion conveys it to the two graded planetary gear system (29, 30) having a definite cycle ratio. Increase in the motor (26) torque is ensured by this gear system (29, 30). High level of torque created by the planetary gear system (29, 30) is conveyed to the part named as spindle (31). Spindle (31), seen in Figure 6 and 7, moves together with a cylindrical part called as guide (32) surrounding the motor (1). It is preferred to use a bearing (33) in the middle of the planetary gear system (29, 30) and the guide (32) in order to provide the transmission of the motion silently and effectively.

As seen in Figure 7, guide (32) is mechanically tied to the threaded tube (35). Indents (36) on the guide (32) are embedded into the channels inside the threaded tube (35). While the guide (32) rotates its own axis thanks to the said connection, it enables the threaded tube (35) rotate with itself and also allows the threaded tube (35) move in the upside and downside directions. The threaded tube (35) moves in the upside and downside directions through the corresponding threads (38) located in the middle of the adapter plate (7). The emerging motion here is not different from the motion of the pair of bolt-nut. Since the service chamber (2) is full with compressed air and flange (4) leans against the non pressure plate (5), threaded tube (35) covers the distance up to the flange (4) rapidly without operating against the load. After this distance is covered, threaded tube (35) leans on the flange (4). Parking brake force produced by air is fixed in this stage. After this stage, the motor (26) stops and air in the service chamber (2) is released. Therefore, parking brake force is fully conveyed to the threaded tube (35) and parking process is completed. Achieved parking brake force is constantly controlled by the load cells (23) on the threaded tube (35) until the system is stationary. In case of any decrease in the amount of load during this period, electrical motor (26) is activated again and targeted parking brake force is achieved. When it is requested to shift the vehicle to non-parking condition, the actuator (1) moves as in the block diagram shown in Figure 10. Firstly compressed air is sent to the service chamber (2) and motor (26) is operated in the reverse direction. The motor (26) which does not work under load covers the stroke distance rapidly and returns to the initial status. Finally, compressed air in the service chamber (2) is released and the vehicle is shifted to the driving condition (Figure 8).

Actuators (1) described with this invention are designed to brake even in case of an air leakage that may occur in the brake system when the vehicle is in the driving condition. Brake force required to stop the vehicle is provided by the motor (26) used and two graded planetary gear system (29, 30). The planetary gear system (29, 30) used hereby decreased the speed of the motor (26) while increasing the torque.

The whole process that is described above is conducted by processing the data in the ECAN (25) interface of the actuator (1). Data like "parking the vehicle" or "shifting the vehicle to the driving condition" sent from the cabin of the vehicle by pressing to a button are disseminated in the vehicle through CAN data line. ECAN interface (25) on the actuator (1) receive these data and allows the actuator (1) to shift to parking condition or non-parking condition in line with the block diagrams in Figure 9 and 10.

Design 3: While producing parking brake force in the electro-mechanical brake actuator (1), that is the subject of the invention, it was mentioned that compressed air and electrical motors (29) operate in combination. Electromechanical brake actuator (1) generally operate according to the following process: when it is requested to take the vehicle in to the parking condition (Figure 12) or driving condition (Figure 13), firstly compressed air is sent to the service chamber (2) of the actuator. This compressed air enables both the creation of parking brake force (while it is undertaking the parking function) and removal of the parking brake force on the plug (8) (while shifting the vehicle to driving condition). The purpose of sending air to the service chamber (2) while taking the vehicle into the driving condition is to avoid the permanent operation of motors (39) under loads. Thus, the lives of the motors (39) are extended. Following the transmission of compressed air to the service chamber (2), electrical motors (39) are activated and either the parking brake force is fixed or fixed parking brake force is removed.

The actuator (1) has another function in addition to the said two functions. This is emergency parking function (Figure 14). Emergency parking function is automatically activated to stop the vehicle at the shortest time in case of breakdown such as air leakage which may occur in the brake lines of the vehicle. During the fulfillment of this function, compressed air and electrical motors (39) do not work simultaneously. Only the electrical motors (39) operate. In other words, brake force required to stop the vehicle is provided by the motors (39). The motors (39) operate in accordance with the predetermined parameters. Within the scope of described 3 functions, motors (39) stop after operating in line with various parameters. Following this stage, parameters (in case the vehicle is shifted to parking condition or emergency parking functions are activated) are regularly controlled until the system becomes stationary. Provided that parameters exceed the definite tolerance intervals, motors (39) are activated again to achieve the target values. When the parameters are stagnant, the function is completed by releasing the air in the service chamber (2). When it is requested to take the vehicle into the driving condition, parameters are verified, air in the service chamber (2) is released immediately and the vehicle is in the driving condition. In all three functions, rotary motions created by the motors (39) are converted in to axial motion by a mechanical system of the actuator (1) and brake force is conveyed initially to the push rod (6) of the actuator (1) and wheels of the vehicle. How the said mechanical system operates is further described as follows:

The system seen in Figure 11 has a gear system especially designed to reduce the speed of the motor (39) and increase the torque. The system comprises two graded planetary gear mechanism (42, 43). Each planetary gear system (42, 43) consists of carrying arms (43b, 45) and planet gears (42a, 43a). Rotary motion of the motors (39) seen in the Figure 11 is firstly transmitted to the motor output shaft (40), affiliated pinion gears (41) and to the main gear (42b). Main gear (42b) is embedded in the power transmission shaft (46); and these two parts (transmission shaft (46) and main gear (42b)) can move independent from each other. As it can be seen in Figure 11, main gear (42b) possesses two different gears. One of these gears is connected to the pinion gears (41) as mentioned above and the other functions as the sun gear (42b) of the first grade planetary gear system (42). Sun gear (42b) of the first grade planetary gear system conveys the motion it receives to the planet gears (42a). Planet gears (42a) operate between the ring gears (44) and sun gears (42b). Planet gears (42a) of the first grade planetary gear system (42) transmit the motion they receive from the main gear (42b) to the sun gear (43b) of the second grade planetary gear system (43) by means of a carrying arm (43b). As seen in Figure 11, carrying arm (43b) of the first grade planetary gear system (42) and sun gear (43b) of second grade planetary gear system (43) are a single piece. This part (43b) is embedded into the power transmission shaft (46) and can rotate independent from the shaft (46). In other words, it is not fixed to the power transmission shaft (46). Similar to the first grade planetary gear system (42), sun gear (43b) conveys the motion it receives firstly to the planet gears (43a). Planet gears (43a) operate between the ring gears (44) and sun gears (43b). The motion on the planet gears (43a) is conveyed to the transmission shaft (46) by means of carrying arm (45). Because carrying arm (45) in this part moves together with the power transmission shaft (46). As the whole load carried by the system is on the said arm (45), carrying arm (45) is embedded on to the housing (50) with a bearing (33) carrying axial load. In other words, the first motion received from the motors (39) is conveyed to the transmission shaft (46) by means of planetary gear systems (42, 43) with decreased speed and increased torque. As it can be seen in Figure 11, the power transmission shaft (46) transmits the motion it receives to the square sectional tube (47) through the threads. Square sectional tube (47) is beared by a square sectional bearing (48) in the centre of the adapter plate (7). The bearing in the centre of the tube (47) and the adapter plate (7) is square sectional in order to allow the upside (x) and downside (y) motion of the tube (47) without rotating.

When it is requested to park the vehicle, shift the vehicle from parking condition (driving condition) or in case of emergency parking condition occurs due to the mechanical breakdown on the vehicle, the designed brake actuator (1) moves according to the block diagram indicated in Figure 12, 13 and 14.

When it is requested to park the vehicle (Figure 12), ECAN message including this request is received by an interface (25) integrated to the brake actuator (1). Following the verification of the message, compressed air is sent from the air inlet (9) to the service chamber (2) of the actuator and electrical motors (39) are activated. While the compressed air fills the chamber (2), diaphragm (3) made of rubber material rotate reversely and pushes forward (x direction) the flange (4) and push rod (6) affiliated to the flange (4). As the flange (4) leans against the non pressure plate (5), required park force is achieved. In the next stage, the exerted brake force is fixed. This process is undertaken by the compressed air sent to the service chamber (2) and simultaneously operating motors (39) pushing the square section tube (47) to which they are affiliated towards x direction and leaning it to the diaphragm (3). During this process, 3 parameters are regularly controlled. The said parameters refer to the applied parking brake force, number of rotation of the transmission shaft (46) the elapsed time while the plug (8) attached to the square section tube (47) leans against the diaphragm (3). Follow-up of these parameters are ensured by the interface (25) integrated to the actuator (1) and load cells (23) on the plug (8). For accurate realization of the process, it is required that all parameters are within the interval of predetermined value. Unless the parameters are fulfilled, the lacking parameter is reported and sent to the ECU (Electronic Control Unit). If these parameters are met, motors (39) are stopped and this information is sent to the ECU. In the next stage, load on the actuator shaft (6) are permanently controlled. In case of any reduction in the amount of load, motors (39) are activated again obtaining the determined parking brake force. The loss in the amount of loads mentioned in this part is detected by the load cells (23) placed specifically on the plug (8). These steps are repeated until the system becomes stationary. Once it is achieved, the air in the service chamber (2) of the actuator (1) is released and the parking process is completed.

When it is requested to shift the vehicle to non-parking condition, the actuator (1) moves in line with the block diagram given in Figure 13. The message including the request to park is received by ECAN (Enhanced Controller Area Network) interface (25) integrated to the actuator. Following the verification of the message, air is sent from to the service chamber (2) of the actuator (1) and electrical motors (39) are activated. The motor (39) then moves in the direction reverse to the parking motion. Upon the operation of the motors (39), square section tube (47) to which the motor (39) is mechanically connected moves in "y" direction and returns to its initial position. During this process, 3 parameters (number of rotation, load and time) are regularly controlled. While this function is being performed, it is required that the value of parameters related to the load be (-). Other parameters remain the same. Unless the parameters are fulfilled, the lacking parameter is reported and sent to the ECU (Electronic Control Unit). If these parameters are met, motors (39) are stopped and this information is sent to the ECU. Finally air in the service chamber (2) is released and the vehicle is shifted to non-parking condition.

In case of an emergency parking condition occurs due to the mechanical breakdown on the vehicle, the actuator (1) moves according to the block diagram indicated in Figure 14. The said mechanical breakdown refers to the air leakages which may be encountered in the air line to the actuator (1). If this condition arises while the vehicle is in motion, actuator (1) shifts to the emergency parking condition and ensures safe stopping of the vehicle. The system works as follows: ECAN interface (25) of the actuator (1) which receives the emergency parking message activates the electrical motors (39). Electrical motors (39) pushes directly square section tube (47) to which the motors (39) are affiliated and indirectly the shaft (6) towards forming the parking brake force. When the brake force is exerted, 3 parameters (number of rotation, load and time) previously mentioned are taken into consideration. Unless the parameters are fulfilled, the lacking parameter is reported and sent to the ECU (Electronic Control Unit). If these parameters are met for this function, motors (39) are stopped and this information is sent to the ECU. Following this process, it is monitored by the load cells (23) on the plug (8) whether there is any loss in the loads until the system becomes stationary. If any loss is detected, motors (39) are activated again and the loss is compensated. Once the system is stationary, motors (39) are stopped and emergency parking process is completed. In conventional systems, a part called release bolt is used to take the brake actuators already in emergency parking position into the driving condition. This part is used to compress the released heavy emergency spring and take the vehicle to driving condition. It is possible to observe such situation in electro-mechanical brake actuators (1). The vehicle may permanently remain in the parking position in a possible power cut. In such case, release nut (49) fixed to the transmission shaft (46) are used to shift the actuators (1) from parking condition. Release nut enables the emergency spring to be caged by being rotated to an appropriate direction by means of a tool.

Claims

CLAIMS - Spring brake actuator having a park chamber driven by electrical motor characterized in that it comprises the following main members to perform the function of air in the park chamber by the force received by an electrical motor:

• Electrical motor (12),

• Pinion gear (20) connected to the motor output shaft (12),

• Planet gears (19) contacted by the pinion gears (20),

• Bearing pins (22) beared by the planet gears (19), • Carrying upper and lower arm (24),

• Stationary ring gear (21) contacted by the planet gears (19),

• Transmission shaft (14) connected to the carrying arms (24),

• Square nut (16) attached to the transmission shaft (14),

• Tube (15) receiving the motion from the square nut (16), • Plug (8),

• Guide plate (18) connected to the tube (15),

• Bearing pins (22),

• Load cells (23) on the plug (8). - Spring brake actuator having a park chamber driven by electrical motor according to the Claim 1, characterized in that the first motion is received from the electrical motor (12) and conveyed initially to the pinion gear (20) attached to the motor output shaft (13) and then to the planet gears (19). - Spring brake actuator having a park chamber driven by electrical motor according to the Claim 1, characterized in that the planet gears (19) are beared between the carrying upper and lower arms (24) through the bearing pins (22) and the said gears (19) can freely rotate between the carrying upper and lower arms (24). 4- Spring brake actuator having a park chamber driven by electrical motor according to any of the preceding claims, characterized in that ring gear (21) contacted by the planet gears (19) are attached to the housing (11) by means of bolts and the said gear (21) is stationary. 5- Spring brake actuator having a park chamber driven by electrical motor according to any of the preceding claims, characterized in that the motion on the planet gears (19) is conveyed to the carrying arms (24) as the ring gear (21) is fixed to the housing (11).

6- Spring brake actuator having a park chamber driven by electrical motor according to any of the preceding claims, characterized in that the rotating carrying arms (24) also rotate the transmission shaft (14) connected to the arms (24).

7- Spring brake actuator having a park chamber driven by electrical motor according to any of the preceding claims, characterized in that the transmission shaft (14) operates corresponding to the square nut (16); square nut (16) is compressed between the guide plate (18) and the tube (15); and the guide plate (18) and the tube (15) is fixed to each other by means of thread.

8- Spring brake actuator having a park chamber driven by electrical motor according to any of the preceding claims, characterized in that guide shafts (17) are fixed on to the ring gear (21); the shafts (17) guide the plate (18) to move in the vertical direction (A or B); and the guide shafts (17) guide the triple system consisting of square nut (18), guide plate and tube (15) not to rotate around its own axis.

9- Spring brake actuator having a park chamber driven by electrical motor (12) according to any of the preceding claims, characterized in that there is a plug

(8) to provide air tightness.

10- Spring brake actuator having a park chamber driven by electrical motor according to any of the preceding claims, characterized in that the triple system consisting of the square nut (16), tube (15) and guide plate (18) move in "A" direction when the transmission shaft (14) rotate in the predetermined direction; plug (8) connected to tube (15) leans against the diaphragm (3) and flange (4) thereby producing the spring force. -Spring brake actuator having a park chamber driven by electrical motor according to any of the preceding claims, characterized in that there are load cells (23) on the plug (8) used to measure the load on the edge of the push rod (6). -Spring brake actuator having a park chamber driven by electrical motor according to any of the preceding claims, characterized in that electrical motors (12) are stopped when the parking brake force measured by the load cells (23) on the plug (8) achieve a predetermined value; it is waited until the system becomes stationary; and electrical motors (12) are activated again and the targeted parking brake force is obtained in case of any decrease in the amount of load during this period. - Spring -brake actuator having a park chamber driven by electrical motor according to any of the preceding claims, characterized in that electrical motors (12) operate in the reverse direction; pinion gear (20), planet gears

(19), carrying arms (24) and transmission shaft (24) rotate reverse to the first motion; the triple system consisting of guide plate (18), square nut (16) and tube (15) move in "B" direction; load on the plug (8) is controlled by the load cells (23); and electrical motors (12) are stopped and process of shifting the vehicle to driving condition is terminated when the load is at "0" value; - Electro-mechanical brake actuator characterized in that it comprises the following main members:

• Electrical motor (26), • diaphragm made of rubber (3),

• flange (4),

• Push rod (6) connected to the flange (4),

• motor shaft (27),

• pinion gear (28) connected to the motor shaft (27), • two graded planetary gear system (29, 30),

• Spindle (31), • guide (32) surrounding the motor (26),

• Threaded tube (35)

• roller bearing (33) between planetary gear system (29, 30) and guide (32),

• adapter plate (7) • Teeth (38) on the adapter plate (7)

• load cells (23) on the threaded tube (35),

• Housing (34),

• ECAN interface (25)

15- Electro-mechanical brake actuator according to Claim 14, characterized in that the compressed air and electrical motor (26) operate in combination during formation of the parking brake force; compressed air is transmitted from air inlet (9) to the service chamber (2) of the actuator when the vehicle is to be parked; compressed air starts to fill in the chamber (2), diaphragm made of rubber (3) turns over to push flange (4) and connected push rod (6) forward; and the parking force requested is obtained with flange (4) leaning against the non pressure plate (5).

16- Electro-mechanical brake actuator according to Claim 14, characterized in that, electrical motor (26) placed on the park side (10) of the vehicle starts to move simultaneously with the air transmitted to the service chamber (2) to park the vehicle, this movement is transmitted primarily to the pinion gear (28) connected to the motor shaft (27) and then to a two graded planetary gear system (29, 30); motor torque is increased through planetary gear system (29, 30); the motion received from the planetary gear system (29, 30) is transmitted to a cylindrical part called guide (16) which surrounds the motor

(26) through a Spindle (31); and a roller bearing (33) is used between the planetary gear system (29, 30) and the guide (32) in order to ensure a silent and effective transmission. 17- Electro-mechanical brake actuator according to Claim 14, 15 or 16 characterized in that the guide (32) is mechanically connected to the threaded tube (35).

18- Electro-mechanical brake actuator according to Claim 14, 15, 16 or 17 characterized in that notches (36) on the guide (32) is embedded to the channels at the inner part of the threaded tube (35); the guide (32) revolving around its own axis rotates the threaded tube (35); and allows upside and downside movement of the threaded tube (35).

19- Electro-mechanical brake actuator according to Claim 14, 15, 16, 17 or 18 characterized by having corresponding threads (38) at the middle of the adapter plate (7) in order to ensure upside and downside movement of the threaded tube (36).

20- Electro-mechanical brake actuator according to Claim 14, 15, 16, 17, 18 or 19 characterized in that service side (2) is full of compressed air and threaded tube (35) rapidly moves towards the flange (4) without making effort against the load as the flange (4) is leant against the non pressure plate (5), after completing this distance, threaded tube (35) leans against the flange (4), and after this stage, the motor (26) stops and air in the service chamber (2) is released, and thus parking process is executed through complete transfer of the parking force to the motor (26).

21- Electro-mechanical brake actuator according to Claim 14, 15, 16, 17, 18, 19 or 20 characterized in that parking brake force created is regularly controlled by the load cells (23) on the threaded tube (35) until the system becomes stationary; and in case of any possible loss in the load during this period, electrical motor (26) is activated and the targeted parking brake force is obtained again. - Electro-mechanical brake actuator according to Claim 14, 15, 16, 17, 18, 19, 20 or 21 characterized in that when the vehicle is to be out of the parking status, compressed air is transmitted to the service chamber (2), and the motor (26) is operated reversely, the motor speedily passes the stroke distance back to its original status with no extra load, and following this, the pressure in the service chamber (2) is released and the vehicle is brought back to driving condition. - Electro-mechanical brake actuator according to Claim 14, 15, 16, 17, 18, 19, 20, 21 or 22 characterized in that the vehicle can brake even in driving condition; and brake force is obtained from two graded planetary gear system (29, 30) and motor (26). - Electro-mechanical brake actuator according to Claim 14, 15, 16, 17, 18, 19, 20, 21, 22 or 23 characterized in that all processes are realized through data processing at the ECAN (25) interface of the actuator (1), "parking" or "non- parking" data sent through pressing a button from the vehicle are transmitted within the vehicle through CAN data line, and ECAN interface (25) on the actuator (1) receiving these data ensures parking or non-parking of the actuator. - Electro-mechanical brake actuator characterized in that it comprises the following main members:

• Electrical motors (39) • Diaphragm (3)

• Flange (4)

• Push rod connected to flange (6)

• Motor output shafts (40)

• Pinion gears connected to motor shaft (41) • First grade planetary gear system (42) consisting of planet gears (42a) of first grade planetary gear system and sun gear (main gear) (42b) of first grade planetary gear system • Second grade planetary gear system (43) consisting of planet gears (43a) of second grade planetary gear system and sun gear (carrying arm) (43b) of two graded planetary gear system

• Power transmission shaft (46) « Ring gear (44)

• Square sectional tube(47)

• Square sectional bearing in the center of adapter plate (48)

• Release nut (49)

• Carrying arm of second grade planetary gear system (45) . ECAN interface (25)

• Plug (8)

. Load cells (23)

26- Electro-mechanical brake actuator according to Claim 25 characterized in that each planetary gear system (42, 43) is made of a carrying arm (43b, 45), sun gear (42b, 43b) and planet gears (42a, 43a) in order to reduce the speed of motor and increase the torque.

27- Electro-mechanical brake actuator according to Claim 25 or 26 characterized in that rotary motion of the motors (39) is conveyed to firstly pinion gears (41) connected to the motor output shaft (40) and then to the main gear (42b).

28- Electro-mechanical brake actuator according to any of the Claim 25 to 27 characterized in that main gear (42b) is beared for the power transmission shaft (46).

29- Electro-mechanical brake actuator according to any of the Claim 25 to 28 characterized in that power transmission shaft (46) and main gear (42b) can move independent from each other.

30- Electro-mechanical brake actuator according to any of the Claim 25 to 29 characterized in that main gear (42b) comprises two different gears, one of which is connected to the pinion gears as mentioned above and the other functions as sun gear (42b) of first grade planetary gear system (42). 31- Electro-mechanical brake actuator according to any of the Claim 25 to 30 characterized in that sun gear (42b) of first grade planetary gear system conveys the motion it receives to the planet gears (42a).

32- Electro-mechanical brake actuator according to any of the Claim 25 to 31 characterized in that planet gears (42a) operate between ring gear (44) and sun gear (42b).

33- Electro-mechanical brake actuator according to any of the Claim 25 to 32 characterized in that planet gears (42a) of first grade planetary gear system convey the motion received from the main gear (42b) to sun gear (43b) of second grade planetary gear system by means of carrying arm (43b).

34- Electro-mechanical brake actuator according to any of the Claim 25 to 33 characterized in that carrying arm (42b) of first grade planetary gear system

(42) and sun gear (43b) of second grade planetary gear system (43) are single piece.

35- Electro-mechanical brake actuator according to any of the Claim 25 to 34 characterized in that sun gear (43b) of second grade planetary gear system

(43) is beared for power transmission shaft (46) and can rotate independent from the shaft (46).

36- Electro-mechanical brake actuator according to any of the Claim 25 to 35 characterized in that sun gear (43b) of second grade planetary gear system (43) conveys the motion received firstly to the planet gears (43a).

37- Electro-mechanical brake actuator according to any of the Claim 25 to 36 characterized in that planet gears (43a) operate between the ring gear (44) and the sun gear (43b).

38- Electro-mechanical brake actuator according to any of the Claim 25 to 37 characterized in that the motion on the planet gears (43a) is transmitted to the power transmission shaft (45) through carrying arm (45). 39- Electro-mechanical brake actuator according to any of the Claim 25 to 38 characterized in that carrying arm (45) and power transmission shaft (46) operate simultaneously.

40- Electro-mechanical brake actuator according to any of the Claim 25 to 39 characterized in that carrying arm (45) is beared on a roller bearing (33) carrying axial load and the housing (50).

41- Electro-mechanical brake actuator according to any of the Claim 25 to 40 characterized in that the first motion received from the motors (39) is conveyed to the power transmission shaft (46) by decreasing its speed and increasing its torque through the planetary gear systems (42, 43).

42- Electro-mechanical brake actuator according to any of the Claim 25 to 41 characterized in that power transmission shaft (46) conveys the motion received to the square sectional tube (47) through threads.

43- Electro-mechanical brake actuator according to any of the Claim 25 to 42 characterized in that square sectional tube (47) is beared by square sectional bearing (33) in the center of the adapter plate (7).

44- Electro-mechanical brake actuator according to any of the Claim 25 to 43 characterized in that compressed air and electrical motors (39) operate in combination when the parking brake force is produced.

45- Electro-mechanical brake actuator according to any of the Claim 25 to 44 characterized in that compressed air is sent to the service chamber (2) of the actuator (1) when it is requested to take the vehicle in to parking condition or drive condition.

46- Electro-mechanical brake actuator according to any of the Claim 25 to 45 characterized in that after sending compressed air to the service chamber (2) when it is requested to take the vehicle to parking or driving condition, electrical motors (39) are activated and parking brake force is fixed or fixed parking brake force is removed. 47- Electro-mechanical brake actuator according to any of the Claim 25 to 46 characterized in that compressed air and electrical motors (39) do not operate simultaneously but only electrical motors (39) functions during emergency parking condition.

48- Electro-mechanical brake actuator according to any of the Claim 25 to 47 characterized in that motors (39) operate according to the predetermined parameters and stop after operating in line with different parameters.

49- Electro-mechanical brake actuator according to any of the Claim 25 to 48 characterized in that provided that parameters exceed predetermined intervals of tolerances, motors (39) are activated again and targeted values are achieved; and the function is completed by releasing the air in the service chamber (2) of the actuator when the parameters become stationary.

50- Electro-mechanical brake actuator according to any of the Claim 25 to 49 characterized in that when the vehicle is taken into driving position, the air in the service chamber (2) is immediately released after the parameters are verified and then the vehicle is shifted to driving condition.

51- Electro-mechanical brake actuator according to any of the Claim 25 to 50 characterized in that in each three functions, rotary motions created by the motor (39) is converted into axial motion by means of the mechanical system of the actuator and transmitted as brake force firstly to the push rod (6) of the actuator and then to the wheels.

52- Electro-mechanical brake actuator according to any of the Claim 25 to 51 characterized in that when it is requested to take the vehicle in to parking condition, ECAN message including this request is received by ECAN interface (25) integrated to the brake actuator (1); compressed air sent to the service chamber (2) of the actuator (1) from the air inlet (9) and the electrical motors (39) are activated after the message is verified; while the compressed air fills in the chamber, diaphragm (3) turns over and pushes forward (x direction) the flange (4) and the push rod (6) connected to the flange (4); the flange (4) leans against the non pressure plate (5); then the air sent to the service chamber (2) and simultaneously operated motors (39) pushes and leans the square section tube (47) in the x direction against the diaphragm (3) in order to fix the brake force; and 3 parameters are regularly controlled during this process.

53- Electro-mechanical brake actuator according to any of the Claim 25 to 52 characterized in that follow-up of parameters are conducted through the ECAN interface (25) integrated to the actuator (1) and the load cells (23) on the plug (8).

54- Electro-mechanical brake actuator according to any of the Claim 25 to 53 characterized in that unless the parameters are fulfilled, the lacking parameter is reported and sent to the ECU (Electronic Control Unit); if these parameters are met, motors (39) are stopped and this information is sent to the ECU; in the following stage, load on the actuator shaft (6) are permanently controlled; in case of any reduction in the amount of load, motors (39) are activated again and obtain the targeted parking brake force.

55- Electro-mechanical brake actuator according to any of the Claim 25 to 54 characterized in that the loss in the amount of loads is detected by the load cells (23) placed specifically on the plug (8); these steps are repeated until the system becomes stationary; and once it is achieved, the air in the service chamber (2) of the actuator (1) is released and the parking process is completed.

56- Electro-mechanical brake actuator according to any of the Claim 25 to 55 characterized in that when it is requested to shift the vehicle to non-parking condition, the message including the request to park is received by ECAN (Enhanced Controller Area Network) interface (25) integrated to the actuator; following the verification of the message, air is sent from to the service chamber (2) of the actuator (1) and electrical motors (39) are activated; the motor (39) then moves in the direction reverse to the parking motion; upon the operation of the motors (39), square section tube (47) to which the motor (39) is mechanically connected moves in "y" direction and returns to its initial position; and during this process, 3 parameters (number of rotation, load and time) are regularly controlled. - Electro-mechanical brake actuator according to the Claim 56 characterized in that while this function is being performed, it is required that the value of parameters related to the load be (-); other parameters remain the same; unless the parameters are fulfilled, the lacking parameter is reported and sent to the ECU (Electronic Control Unit); if these parameters are met, motors (39) are stopped and this information is sent to the ECU.; and finally air in the service chamber (2) is released and the vehicle is shifted to non-parking condition. - Electro-mechanical brake actuator according to any of the Claim 25 to 57 characterized in that in case of an emergency parking condition occurs due to the mechanical breakdown on the vehicle, ECAN interface (25) of the actuator (1) which receives the emergency parking message activates the electrical motors (39); electrical motors (39) pushes directly square section tube (47) to which the motors (39) are affiliated and indirectly the push rod (6) towards forming the parking brake force; when the brake force is exerted, 3 parameters (number of rotation, load and time) are taken into consideration; unless the parameters are fulfilled, the lacking parameter is reported and sent to the ECU (Electronic Control Unit); if these parameters are met for this function, motors (39) are stopped and this information is sent to the ECU; then it is monitored by the load cells (23) on the plug (8) whether there is any loss in the loads until the system becomes stationary; and if any loss is detected, motors (39) are activated again and the loss is compensated. - Electro-mechanical brake actuator according to any of the Claim 25 to 58 characterized in that it has release nuts (49) fixed to the power transmission shaft (46) in order to avoid the vehicle from permanently remaining in the parking condition in case of a possible power cut.